Metal bending machine



A ril 18, 1939. S, BR N 2,155,160

METAL BENDING MACHINE Filed Oct. 22, 1957 2 Sheets-Sheet l April 18, 1939. s. J. BRUNO 2,155,160

METAL BENDING MACHINE Filed Oct. 22, 1957 2 SheetsSheet 2 22 5 Z7; a,; w 17 6* v s l I a i L? a I r 25 NVENTOR Patented Apr. 18, 1939 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates in general to machines for bending metal bars, and more particularly to machines especially suited for bending angle bars. For many purposes it is desirable to bend wrought metal angle bars, in some cases with one flange or leg of the angle projecting edgewise from the outer or convex side of the bend and in other cases with one flange or leg projecting edgewise from the inner or concave side of the bend. With the heretofore known bending machines, it has been extremely diflicult, if not impossible, to bend an angle bar without throwing the two legs or flanges of the bar out of the desired angular relation to each other, or without bending or deforming the bar in a plurality of angularly disposed directions instead of only in the direction in which it is desired to bend the bar.

I have discovered that this difficulty is due to the stretching or bending of the flanges of the angle bar in diiferent degrees along the free edges of the flanges and at the juncture of the flanges. Therefore, an object of my invention is to provide a novel and improved method and machine of the character described whereby angle bars and the like can be accurately bent with a minimum of undesired distortion of the flanges.

Another object of my invention is to provide a machine which shall embody novel and improved features of construction for stretching or bending the bar in the direction in which it is desired to bend it and simultaneously stretching or bending the bar in a direction at right angles to the direction of intended bending, whereby the stretching in the second mentioned, direction shall compensate for and overcome unintended distortion of the bar which would otherwise result from bending in the intended direction.

Other objects, advantages and results of the invention will appear from the following description when read in conjunction with the following drawings in which Figure 1 is a fragmentary plan view of a metal bending machine embodying my invention.

Figure 2 is a vertical longitudinal sectional view on the line 2-2 of Figure 1.

Figure 3 is a similar view on the line 3--3 of Figure 1.

Figure 4 is a transverse vertical sectional View on the line 4-4 of Figure 3.

Figure 5 is a sectional view on the line 5-5 of Figure 4.

Figure 6 is a sectional view on the line 6-6 of Figure 5.

Figure '7 is a detached perspective view of one of the shoes of the compensating die shown in Figures 6 and 7, and

Figures 8 and 9 are views similar to Figures 2 and 1 respectively, showing a modification of the invention.

Specifically describing the invention, the machine comprises a bed A on which is mounted a bolster B held immovable in opposed relation to a ram C by posts D secured to and projecting upwardly from the bed.

The ram is of a known hydraulic type including a cylinder l and a piston 2 which has an arm 3 projecting upwardly through a slot 4 in the bed in spaced opposed relation to the bolster B for carrying one of the complemental bending dies. is well known in the art.

My invention includes bending and compensating dies cooperating with the ram 0 and bolster B. As shown, one of the bending dies includes a block set upon the bed A in abutting relation to the bolster B. This block is approximately U-shaped in plan view and has two spaced bearing arms 6 or abutments vertically disposed.

Cooperating with the die 5 is a complemental die including a block I vertically slidably mounted in a guide 8 which is in turn removably mounted, as by a dovetail joint 9, on the arm 3. The block 1 is disposed between the bearing arms 6 of the die 5 and has an inclined or beveled bottom surface It slidable upon a correspondingly inclined or beveled rest H on the die 5. With this construction, it will be observed that upon reciprocation of the piston 2 of the cam C, the die block I will be moved horizontally toward and from the die block 5 and at the same time will be moved vertically by relative sliding of the two surfaces II] and H.

The die block 1 serves as a support for interchangeable bending blocks one of which is designated l2 in. Figures 1 to 4 inclusive. This bending block is especially designed for bending the angle bar E with one flange projecting edgewise from the outer or convex side of the bend. The die block 1 has a seat I5 for the bending block l2 and as shown the bending block has flanges l3 separably secured to the die block 1 by bolts or removable pins M. The bending block also has a slot IE to receive the vertical flange of the angle bar E to be bent, the top of the bending block serving as a rest for the horizontal flange of the angle bar.

In operation of the structure so far described, it will be seen that with the angle bars disposed The mechanism so far described I in the bending block as illustrated in Figures 1 to 4 inclusive, upon movement of the die block 1 toward the .die block 5, the free edge of the horizontal flange of the angle bar will abut the bearing arms 6 of the die block 5 at opposite sides of the bending block I2, and continued movement of the die block I under the influence of the ram C will bend the angle bar, with the free edge of the horizontal flange of the angle bar at the outer or convex side of the bend.

Means is also provided for stretching or bending the bar in a vertical direction to compensate the distorting effect of bending the bar in the horizontal direction. As shown, this compensating means includes a pair of abutments F, one at each side of and above the bending block l2 and preferably in approximately the same vertical plane with each of thebearing arms 6. Each abutment F is shown as comprising a lateral hanger I! preferably formed integral with the die block 5, and a shoe [8 mounted in the hanger to oscillate about a horizontal axis parallel to the general plane of the bending of the angle bar. As shown, each shoe includes a face plate 19 and a cylindrical rib 29 disposed along the longitudinal median plane of the back of the face plate and rotatably mounted in a recess 2| in the corresponding hanger l1. For inserting the shoes into the hangers I! the recesses 2| may be cut through the ends of the hangers to permit the ribs 20 to beslipped endwise into the recesses, and cap plates 22 may be applied to the hangers to close the recesses and hold the shoes against displacement.

In operation of the compensating means, as the die block 1 moves toward the die block 5 to bend the angle in the desired horizontal direction, the die block I and bending block I2 are simultaneously moved vertically by engagement of the inclined surfaces I0 and H so as to force the angle bar into engagement with the shoes l8 and stretch or bend the bar in a vertical direction.

During the horizontal bending, the portions of the bar bearing on the shoes l8 tend to move longitudinally of the shoes, and to freely permit this and prevent binding of the bar or scraping of the bar over the shoes, the ribs 20 slide in the recesses 2| to permit movement of the shoes with the bar. Springs 23 are provided for normally influencing the shoes in the other direction into the position shown in Figure 5.

During the vertical stretching action, the parts of the bar bearing on the shoes tend to move longitudinally of the bar which is freely permitted by swinging of the shoes l8, and preferably springs 28 are provided to hold the shoes in positions intermediate their limits of swinging movement. Consequently the angle bar is simultaneously bent in the direction intended and in a direction at right angles thereto. This bending or stretching of the bar simultaneously in two directions ensures against throwing of the flanges of the bar out of perpendicular relation to each other and also ensures against distortion or rippling of the flanges. In other Words, the bending or stretching in one direction compensates the bending or stretching in the other direction.

Figures 8 and 9 show a modification of the machine for bending the angle bar G with one flange projecting edgewise at the inner or concave side of the bend. In this form of the invention the structure is identical with that above described with the exception that the bending blocks are different. Instead of the bending block I2, I utilize a main block 24 which is shown as separably secured by bolts 25 on the die block 1 and forms a seat for the horizontal or inwardly projecting flange of the angle bar. Another bending block 26 is interposed between the die block I and the edge of the horizontal flange of the angle bar, while a third bending block 21 is interposed between the bending block 26 and the vertical'flange of the angle bar.

In operation of the machine, as the die block I is moved toward the die block 5, the vertical flange of the angle bar G is forced against the bearing arms 6, and the bending blocks 26 and 21 transmit pressure from the die block I to bend the angle bar in the direction desired. Simultaneously the edge of the vertical flange of the angle bar is forced against the shoes l8 of the compensating means. The effect on the angle bar is substantially the same as that described in connection with Figures 1 to 7 inclusive, all tendency of the bar to be distorted or bent in other directions than that intended being overcome.

It will be understood that the bending die I may be moved at different relative rates in the vertical and horizontal directions so as to ensure proper relative degrees of bending in the two directions. Also it will be understood that the sizes and shapes of the bending blocks I2, 24, 26 and 2? will vary with the sizes and shapes of the bars to be bent, it being necessary merely to interchange the bending blocks on the die block I to accommodate different bars.

While I have shown and described the invention as embodied in certain details of structure and in a certain type of bending machine, it should be un-derstod that this is primarily for the purpose of illustrating the principles of the invention, and that the invention could be embodied in other types of bending machines and in other details of construction without departing from the spirit or scope of the invention.

Having thus described my invention, what I claim is:

1. A bending machine comprising a power operated reciprocable member, a pair of cooperating dies to receive a bar to be bent between them, I

.vertical and horizontal directions.

2. A bending machine comprising a power operated reciprocable member, a pair of cooperating dies to receive a bar to be bent between them, one die having a pair of spaced vertical abutments and a pair of spaced horizontal abutments and the other die being mounted on said member for horizontal movement therewith and vertical movement relatively thereto, the second mentioned die to engage said bar between the abutments of each pair of abutments, and said dies having slidably cooperating inclined surfaces to cause movement of the second-mentioned die vertically simultaneously with horizontal movement thereof.

3. The bending machine set forth in claim 1 wherein said bending die includes interchangeable bending blocks for transmitting pressurev from said power operated means simultaneously to the vertical and horizontal flanges of an angle bar to be bent.

4. A bending machine of the character described comprising a pair of spaced vertical abutments and a pair of spaced horizontal abutments, a bending die to receive between itself and said abutments a bar to be bent and adapted to engage said bar between the abutments of each pair, a horizontally movable member on which said bending die is mounted for vertical movement, means for moving said member and said die horizontally, and a second member having an inclined surface, said bending die having an inclined surface slidably cooperating with said inclined surface on said second member for moving the die vertically simultaneously with horizontal movement thereof.

5. A machine for bending an angle bar having a vertical flange and a horizontal flange, said machine comprising a pair of spaced vertical abutments and a pair of spaced horizontal abutments, a bending die movable in both horizontal and vertical directions to receive between itself and said abutments an angle bar to be bent and adapted to engage said bar between said abutments of each pair, said bending die having a vertically disposed face and a horizontally disposed face each to engage one flange of said angle bar, means foiimpressing a horizontally directed force onsaid bending die and means cooperating with said die while the die is under influence of said horizontally directed force for impressing a vertically directed force on said die, whereby to move said die and bend the bar simultaneously in vertical and horizontal directions.

6. The bending machine set forth in claim 5 wherein the last two means are correlated so that the rates of movement of said die under said vertically and horizontally directed forces are different, whereby tendency to distortion of the bar by the bending in one direction is compensated by the bending of the bar in the other direction.

7. The bending machine set forth in claim 5 with the addition of shoes to be abutted by said bar and one mounted on each horizontal abutment for limited horizontal movement in directions perpendicular to each other to permit free horizontal movement of the bar relative to the horizontal abutments.

SAMUEL J. BRUNO. 

